with extends, How do we merge children of an element that are not elements themselves

<?xml version="1.0"?>
<cdl:cdl 
  xmlns:cdl="http://www.gridforum.org/namespaces/2005/02/cddlm/CDL-1.0"
 >
  <cdl:configuration>
    <Component>
      <!-- Component: nested comment -->
      Component: Nested Text
    </Component>
  </cdl:configuration>
  <cdl:system>
    <Extension cdl:extends="Component">
      <!-- Extension : nested comment -->
      Extension : Nested Text
    </Extension>
  </cdl:system>
  
</cdl:cdl>


Should it be parent retains stuff:

    <Extension cdl:extends="Component">
      <!-- Extension : nested comment -->
      Extension : Nested Text
    </Extension>

or merge in children
    <Extension cdl:extends="Component">
      <!-- Extension : nested comment -->
      Extension : Nested Text
      <!-- Component: nested comment -->
      Component: Nested Text
    </Extension>
.